Support is requested for a multi-station auditory-visual testing system to be used by a group of investigators in the Department of Speech and Hearing Sciences and their colleagues in other departments at Indiana University. Two double-walled sound-treated chambers will be installed to house the new equipment, using funds from Indiana University. The large sound-treated rooms will enable threshold-level sound intensities to be presented via headphones to as many as ten participants simultaneously. This proposal seeks funds to equip the chambers with a system of networked computers and integrated equipment for auditory and visual stimulus presentation and data collection. Each testing station will be equipped with a 17" high-resolution color monitor, keyboard and mouse, as well as a microphone for voice recording. These components from each testing station will be connected to separate Pentium III, 600-MHZ computers with accompanying electronic equipment needed for sophisticated listening experiments (programmable attenuators with >96 dB signal-to-noise ratios; multi-channel, 16-bit, digital-to- analog converters with signal-processing array processors). The ten computers (one per testing station) will be housed in a separate room outside the double-walled booth to minimize internally generated noise in the test area. The newly equipped laboratory will serve as a multi-purpose group testing facility for a wide variety of research projects in hearing and speech sciences. The projects include studies of multi-sensory changes associated with aging, individual differences in auditory and auditory-visual abilities, speech perception and production, language development, and adult neurogenic communication disorders. The requested equipment will allow a very productive group of researchers to conduct a wider range of research with much greater efficiency.